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Combaluzier S, Quessada J, Abbou N, Arcani R, Tichadou A, Gabert J, Costello R, Loosveld M, Venton G, Berda-Haddad Y. Cytological Diagnosis of Classic Myeloproliferative Neoplasms at the Age of Molecular Biology. Cells 2023; 12:cells12060946. [PMID: 36980287 PMCID: PMC10047531 DOI: 10.3390/cells12060946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/14/2023] [Accepted: 03/16/2023] [Indexed: 03/30/2023] Open
Abstract
Myeloproliferative neoplasms (MPN) are clonal hematopoietic stem cell-derived disorders characterized by uncontrolled proliferation of differentiated myeloid cells. Two main groups of MPN, BCR::ABL1-positive (Chronic Myeloid Leukemia) and BCR::ABL1-negative (Polycythemia Vera, Essential Thrombocytosis, Primary Myelofibrosis) are distinguished. For many years, cytomorphologic and histologic features were the only proof of MPN and attempted to distinguish the different entities of the subgroup BCR::ABL1-negative MPN. World Health Organization (WHO) classification of myeloid neoplasms evolves over the years and increasingly considers molecular abnormalities to prove the clonal hematopoiesis. In addition to morphological clues, the detection of JAK2, MPL and CALR mutations are considered driver events belonging to the major diagnostic criteria of BCR::ABL1-negative MPN. This highlights the preponderant place of molecular features in the MPN diagnosis. Moreover, the advent of next-generation sequencing (NGS) allowed the identification of additional somatic mutations involved in clonal hematopoiesis and playing a role in the prognosis of MPN. Nowadays, careful cytomorphology and molecular biology are inseparable and complementary to provide a specific diagnosis and to permit the best follow-up of these diseases.
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Affiliation(s)
- Sophie Combaluzier
- Hematology Laboratory, Timone University Hospital, 13005 Marseille, France
| | - Julie Quessada
- Hematological Cytogenetics Laboratory, Timone University Hospital, 13005 Marseille, France
- CNRS, INSERM, CIML, Luminy Campus, Aix-Marseille University, 13009 Marseille, France
| | - Norman Abbou
- Molecular Biology Laboratory, North University Hospital, 13015 Marseille, France
- INSERM, INRAE, C2VN, Luminy Campus, Aix-Marseille University, 13005 Marseille, France
| | - Robin Arcani
- INSERM, INRAE, C2VN, Luminy Campus, Aix-Marseille University, 13005 Marseille, France
- Department of Internal Medicine, Timone University Hospital, 13005 Marseille, France
| | - Antoine Tichadou
- Hematology and Cellular Therapy Department, Conception University Hospital, 13005 Marseille, France
| | - Jean Gabert
- Molecular Biology Laboratory, North University Hospital, 13015 Marseille, France
| | - Régis Costello
- INSERM, INRAE, C2VN, Luminy Campus, Aix-Marseille University, 13005 Marseille, France
- Hematology and Cellular Therapy Department, Conception University Hospital, 13005 Marseille, France
- TAGC, INSERM, UMR1090, Luminy Campus, Aix-Marseille University, 13005 Marseille, France
| | - Marie Loosveld
- Hematology Laboratory, Timone University Hospital, 13005 Marseille, France
- Hematological Cytogenetics Laboratory, Timone University Hospital, 13005 Marseille, France
- CNRS, INSERM, CIML, Luminy Campus, Aix-Marseille University, 13009 Marseille, France
| | - Geoffroy Venton
- INSERM, INRAE, C2VN, Luminy Campus, Aix-Marseille University, 13005 Marseille, France
- Hematology and Cellular Therapy Department, Conception University Hospital, 13005 Marseille, France
- TAGC, INSERM, UMR1090, Luminy Campus, Aix-Marseille University, 13005 Marseille, France
| | - Yaël Berda-Haddad
- Hematology Laboratory, Timone University Hospital, 13005 Marseille, France
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Nathan DI, Feld J, El Jamal SM, Mascarenhas J, Tremblay D. Myelodysplastic syndrome/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis: Ringing in a new future. Leuk Res 2022; 115:106820. [DOI: 10.1016/j.leukres.2022.106820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 01/19/2023]
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Easwar A, Siddon AJ. Genetic Landscape of Myeloproliferative Neoplasms with an Emphasis on Molecular Diagnostic Laboratory Testing. Life (Basel) 2021; 11:1158. [PMID: 34833034 PMCID: PMC8625510 DOI: 10.3390/life11111158] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/18/2021] [Accepted: 10/27/2021] [Indexed: 12/27/2022] Open
Abstract
Chronic myeloproliferative neoplasms (MPNs) are hematopoietic stem cell neoplasms with driver events including the BCR-ABL1 translocation leading to a diagnosis of chronic myeloid leukemia (CML), or somatic mutations in JAK2, CALR, or MPL resulting in Philadelphia-chromosome-negative MPNs with constitutive activation of the JAK-STAT signaling pathway. In the Philadelphia-chromosome-negative MPNs, modern sequencing panels have identified a vast molecular landscape including additional mutations in genes involved in splicing, signal transduction, DNA methylation, and chromatin modification such as ASXL1, SF3B1, SRSF2, and U2AF1. These additional mutations often influence prognosis in MPNs and therefore are increasingly important for risk stratification. This review focuses on the molecular alterations within the WHO classification of MPNs and laboratory testing used for diagnosis.
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Affiliation(s)
- Arti Easwar
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT 06510, USA;
| | - Alexa J. Siddon
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT 06510, USA;
- Department of Pathology, Yale School of Medicine, New Haven, CT 06510, USA
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Shallis RM, Zeidan AM. Myelodysplastic/myeloproliferative neoplasm, unclassifiable (MDS/MPN-U): More than just a "catch-all" term? Best Pract Res Clin Haematol 2019; 33:101132. [PMID: 32460977 DOI: 10.1016/j.beha.2019.101132] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 11/29/2019] [Accepted: 12/02/2019] [Indexed: 12/17/2022]
Abstract
The clinicopathology of MDS and MPN are not mutually exclusive and for this reason the category of myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN) exists. Several sub-entities have been included under the MDS/MPN umbrella, including MDS/MPN-unclassifiable (MDS/MPN-U) for those cases whose morphologic and clinical phenotype do not meet criteria to be classified as any other MDS/MPN sub-entity. Though potentially regarded as a wastebasket diagnosis, since its integration into myeloid disease classification, MDS/MPN-U has been refined with increasing understanding of the mutational and genomic events that drive particular clinicopathologic phenotypes, even within MDS/MPN-U. The prototypical example is the identification of SF3B1 mutations and its durable association with MDS/MPN with ring sideroblasts and thrombocytosis (MDS/MPN-RS-T), an entity previously buried within, but now a separate category outside of MDS/MPN-U. Continued and enhanced study of those entities under MDS/MPN-U, a perhaps provisional category itself, is likely to progressively identify commonality between many "unclassifiables" to establish a new classifiable diagnosis.
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Affiliation(s)
- Rory M Shallis
- Section of Hematology, Department of Internal Medicine, Yale University School of Medicine, New Haven, USA; Yale Cancer Center, New Haven, USA.
| | - Amer M Zeidan
- Section of Hematology, Department of Internal Medicine, Yale University School of Medicine, New Haven, USA; Yale Cancer Center, New Haven, USA
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Loghavi S, Wang SA. Defining the Boundary Between Myelodysplastic Syndromes and Myeloproliferative Neoplasms. Surg Pathol Clin 2019; 12:651-669. [PMID: 31352979 DOI: 10.1016/j.path.2019.03.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this article we provide a practical and comprehensive review of myeloid neoplasms with overlapping myelodysplastic (MDS) and myeloproliferative (MPN) features, with emphasis on recent updates in classification, particularly the utility of morphologic, cytogenetic, and molecular findings in better defining and classifying these disease entities. We provide the reader with a summary of the most recent developments and updates that have helped further our understanding of the genomic landscape, clinicopathologic features, and prognostic elements of myeloid neoplasms with MDS/MPN features.
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Affiliation(s)
- Sanam Loghavi
- Department of Hematopathology, The University of Texas, MD Anderson Cancer Center, Houston, TX, USA
| | - Sa A Wang
- Department of Hematopathology, The University of Texas, MD Anderson Cancer Center, Houston, TX, USA.
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Patnaik MM, Tefferi A. Refractory anemia with ring sideroblasts (RARS) and RARS with thrombocytosis: "2019 Update on Diagnosis, Risk-stratification, and Management". Am J Hematol 2019; 94:475-488. [PMID: 30618061 DOI: 10.1002/ajh.25397] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 01/02/2019] [Indexed: 12/17/2022]
Abstract
DISEASE OVERVIEW Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include refractory anemia with ring sideroblasts (RARS), now classified under myelodysplastic syndromes with RS (MDS-RS) and RARS with thrombocytosis (RARS-T); now called myelodysplastic/myeloproliferative neoplasm with RS and thrombocytosis (MDS/MPN-RS-T). DIAGNOSIS MDS-RS is a lower-risk MDS, with single or multilineage dysplasia (SLD/MLD), <5% bone marrow (BM) blasts and ≥ 15% BM RS (≥5% in the presence of SF3B1 mutations). MDS/MPN-RS-T, now a formal entity in the MDS/MPN overlap syndromes, has diagnostic features of MDS-RS-SLD, along with a platelet count ≥450 × 10(9)/L and large atypical megakaryocytes. MUTATIONS AND KARYOTYPE Mutations in SF3B1 are seen in ≥80% of patients with MDS-RS-SLD and MDS/MPN-RS-T, and strongly correlate with the presence of BM RS; MDS/MPN-RS-T patients also demonstrate JAK2V617F, ASXL1, DNMT3A, SETBP1, and TET2 mutations. Cytogenetic abnormalities are uncommon in both. RISK STRATIFICATION Most patients with MDS-RS-SLD are stratified into lower-risk groups by the revised-IPSS. Disease outcome in MDS/MPN-RS-T is better than that of MDS-RS-SLD, but worse than that of essential thrombocythemia. Both diseases have a low risk of leukemic transformation. TREATMENT Anemia and iron overload are complications seen in both and are managed similar to lower-risk MDS and MPN. The advent of luspatercept, a first-in-class erythroid maturation agent will tremendously boost the ability to manage anemia. Aspirin therapy is reasonable in MDS/MPN-RS-T, especially in the presence of JAK2V617F, but the value of platelet-lowering drugs remains uncertain.
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Affiliation(s)
- Mrinal M. Patnaik
- Division of Hematology, Department of Internal Medicine Mayo Clinic Rochester Minnesota
| | - Ayalew Tefferi
- Division of Hematology, Department of Internal Medicine Mayo Clinic Rochester Minnesota
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Li P, Shahmarvand N, Lynch D, Gotlib JR, Merker JD, Zehnder JL, George TI, Ohgami RS. Revisiting diagnostic criteria for myelodysplastic/myeloproliferative neoplasms with ring sideroblasts and thrombocytosis: Borderline cases without anemia exist. Int J Lab Hematol 2019; 41:345-352. [PMID: 30811101 DOI: 10.1111/ijlh.12981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 12/31/2018] [Accepted: 01/07/2019] [Indexed: 12/26/2022]
Abstract
INTRODUCTION Myelodysplastic/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis (MDS/MPN-RS-T) is a rare disease in the 2016 revised World Health Organization (WHO) classification. Diagnostic criteria include the following: persistent thrombocytosis (>450 × 109 /L) with clustering of atypical megakaryocytes, refractory anemia, dyserythropoiesis with ring sideroblasts, and the presence of the spliceosome factor 3b subunit (SF3B1) mutation. It is unclear if anemia should be a required criterion for this diagnosis as cases which show all other features of MDS/MPN-RS-T but without anemia exist. METHODS We searched for borderline cases of MDS/MPN-RS-T in which refractory anemia was absent at diagnosis in two major academic institutes. RESULTS Three cases without anemia were identified. These cases all showed other classic morphologic and clinical features of MDS/MPN-RS-T, including thrombocytosis, atypical megakaryocytes with clustering, and characteristic SF3B1 and JAK2 V617F mutations. CONCLUSION Given these findings, the requirement of refractory anemia as a diagnostic criterion for MDS/MPN-RS-T should be re-evaluated. Removal of refractory anemia as a diagnostic criterion would incorporate current borderline cases and extend the spectrum of this disorder.
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Affiliation(s)
- Peng Li
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida
| | - Nahid Shahmarvand
- Department of Pathology, Stanford University Medical Center, Stanford, California
| | - David Lynch
- Department of Pathology, Brooke Army Medical Center, San Antonio, Texas
| | - Jason R Gotlib
- Department of Pathology, Stanford University Medical Center, Stanford, California.,Department of Medicine, Stanford University Medical Center, Stanford, California
| | - Jason D Merker
- Department of Pathology, Stanford University Medical Center, Stanford, California.,University of North Carolina, Chapel Hill, North Carolina
| | - James L Zehnder
- Department of Pathology, Stanford University Medical Center, Stanford, California.,Department of Medicine, Stanford University Medical Center, Stanford, California
| | - Tracy I George
- University of Utah, Salt Lake City, Utah.,Department of Pathology, University of New Mexico, Albuquerque, New Mexico
| | - Robert S Ohgami
- Department of Pathology, Stanford University Medical Center, Stanford, California
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Hu Z, Ramos CEB, Medeiros LJ, Zhao C, Yin CC, Li S, Hu S, Wang W, Thakral B, Xu J, Verstovsek S, Lin P. Utility of JAK2 V617F allelic burden in distinguishing chronic myelomonocytic Leukemia from Primary myelofibrosis with monocytosis. Hum Pathol 2018; 85:290-298. [PMID: 30447300 DOI: 10.1016/j.humpath.2018.10.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 10/30/2018] [Accepted: 10/31/2018] [Indexed: 01/11/2023]
Abstract
The concurrent presence of JAK2 V617F, monocytosis, and bone marrow fibrosis can be observed in both chronic myelomonocytic leukemia (CMML) and primary myelofibrosis (PMF). It can be challenging to distinguish CMML with JAK2 mutation and fibrosis from other myeloid neoplasms, particularly PMF. To identify key features that may help distinguish these 2 entities, we retrospectively studied 21 cases diagnosed as "CMML" with JAK2 V617F and bone marrow fibrosis that were identified from a cohort of 610 cases of CMML diagnosed in 2006 to 2016. Upon further review, we confirmed the diagnosis of CMML in 7 cases, 11 cases were reclassified as PMF, and 3 cases had features intermediate between CMML and PMF (gray zone). These 11 cases of PMF with monocytosis featured a higher JAK2 V617F allelic burden (median, 43%; range, 20%-62%) and atypical pleomorphic megakaryocytes with hyperchromatic nuclei. Complete blood count showed more pronounced myeloid left shift. In contrast, 7 CMML cases had significantly lower JAK2 V617F allelic burden (median, 17%; range, 5%-36%; P < .0001) and dysplastic megakaryocytes along with variable degree of dysplasia in other lineages. The median survival of PMF and CMML patients was 32 and 40 months, respectively. We conclude that besides morphology of megakaryocytes and other features, JAK2 V617F allelic burden can help differentiate CMML from PMF with monocytosis. SRSF2 and RAS mutations are observed in both disease categories. Rare gray-zone cases exist with hybrid features.
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Affiliation(s)
- Zhihong Hu
- Department of Pathology and Lab Medicine, The University of Texas Health Center at Houston, Houston, TX 77030, USA
| | - Carlos E Bueso Ramos
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - L Jeffrey Medeiros
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Chong Zhao
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - C Cameron Yin
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Shaoying Li
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Shimin Hu
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Wei Wang
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Beenu Thakral
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Jie Xu
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Srdan Verstovsek
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Pei Lin
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
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Kumar A, Jain M, Kushwaha R, Singh US. Anemia with thrombocytosis in an elderly male: a case of myelodysplastic syndrome-myeloproliferative neoplasm with ringed sideroblasts and thrombocytosis. Hematol Transfus Cell Ther 2018; 40:385-388. [PMID: 30370419 PMCID: PMC6200679 DOI: 10.1016/j.htct.2018.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 02/22/2018] [Indexed: 11/16/2022] Open
Affiliation(s)
| | - Mili Jain
- King George's Medical University, Lucknow, UP, India
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Alshaban A, Padilla O, Philipovskiy A, Corral J, McAlice M, Gaur S. Lenalidomide induced durable remission in a patient with MDS/MPN-with ring sideroblasts and thrombocytosis with associated 5q- syndrome. Leuk Res Rep 2018; 10:37-40. [PMID: 30186759 PMCID: PMC6122386 DOI: 10.1016/j.lrr.2018.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 08/07/2018] [Accepted: 08/16/2018] [Indexed: 01/19/2023] Open
Abstract
We describe a patient with MDS/MPN with ring sideroblasts and thrombocytosis who had deletions of long arm of chromosome 5 (5q-) and chromosome 20 (20q-). Molecular studies showed an exon 9, frame shift mutation in the calreticulin (CALR) gene, and absence of mutations in JAK2, MPL, SETBP1 or SF3B1. Treatment with lenalidomide resulted in durable clinical remission which has lasted 2 years.
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Affiliation(s)
- Ahmed Alshaban
- Department of Medicine, Texas Tech University Health Sciences Center Paul L. Foster School of Medicine, El Paso, TX, USA
| | - Osvaldo Padilla
- Department of Pathology, Texas Tech University Health Sciences Center Paul L. Foster School of Medicine, El Paso, TX, USA
| | - Alexander Philipovskiy
- Department of Medicine, Texas Tech University Health Sciences Center Paul L. Foster School of Medicine, El Paso, TX, USA
| | - Javier Corral
- Department of Medicine, Texas Tech University Health Sciences Center Paul L. Foster School of Medicine, El Paso, TX, USA
| | - Meghan McAlice
- Department of Medicine, Texas Tech University Health Sciences Center Paul L. Foster School of Medicine, El Paso, TX, USA
| | - Sumit Gaur
- Department of Medicine, Texas Tech University Health Sciences Center Paul L. Foster School of Medicine, El Paso, TX, USA
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Wang HY, Dell'Aquila ML, Dvanajscak Z, Bejar R, Broome HE, Hsi E, Murray SS, Thorson JA. JAK2 double minutes with resultant simultaneous amplification of JAK2 and CD274 in a therapy-related myelodysplastic syndrome evolving into an acute myeloid leukaemia. Br J Haematol 2018; 185:566-570. [PMID: 30132795 DOI: 10.1111/bjh.15538] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Huan-You Wang
- Division of Laboratory and Genomic Medicine, Department of Pathology, University of California San Diego, La Jolla, CA, USA
| | - Marie L Dell'Aquila
- Division of Medical Genetics, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Zeljko Dvanajscak
- Division of Laboratory and Genomic Medicine, Department of Pathology, University of California San Diego, La Jolla, CA, USA
| | - Rafael Bejar
- Division of Hematology and Oncology, Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - H Elizabeth Broome
- Division of Laboratory and Genomic Medicine, Department of Pathology, University of California San Diego, La Jolla, CA, USA
| | - Eric Hsi
- Department of Pathology and Clinical Medicine, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Sarah S Murray
- Division of Laboratory and Genomic Medicine, Department of Pathology, University of California San Diego, La Jolla, CA, USA
| | - John A Thorson
- Division of Laboratory and Genomic Medicine, Department of Pathology, University of California San Diego, La Jolla, CA, USA
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Al-Kali A, Abou Hussein AK, Patnaik M, Zblewski D, Gangat N, Hashmi S, Elliott M, Hogan W, Litzow M. Hypomethylating agents (HMAs) effect on myelodysplastic/myeloproliferative neoplasm unclassifiable (MDS/MPN-U): single institution experience. Leuk Lymphoma 2018; 59:2737-2739. [PMID: 29465270 DOI: 10.1080/10428194.2018.1436705] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Aref Al-Kali
- a Division of Hematology , Mayo Clinic , Rochester , MN , USA
| | | | - Mrinal Patnaik
- a Division of Hematology , Mayo Clinic , Rochester , MN , USA
| | - Darci Zblewski
- a Division of Hematology , Mayo Clinic , Rochester , MN , USA
| | - Naseema Gangat
- a Division of Hematology , Mayo Clinic , Rochester , MN , USA
| | - Shahrukh Hashmi
- a Division of Hematology , Mayo Clinic , Rochester , MN , USA
| | | | - William Hogan
- a Division of Hematology , Mayo Clinic , Rochester , MN , USA
| | - Mark Litzow
- a Division of Hematology , Mayo Clinic , Rochester , MN , USA
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Maciejewski JP, Balasubramanian SK. Clinical implications of somatic mutations in aplastic anemia and myelodysplastic syndrome in genomic age. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2017; 2017:66-72. [PMID: 29222238 PMCID: PMC6142555 DOI: 10.1182/asheducation-2017.1.66] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Recent technological advances in genomics have led to the discovery of new somatic mutations and have brought deeper insights into clonal diversity. This discovery has changed not only the understanding of disease mechanisms but also the diagnostics and clinical management of bone marrow failure. The clinical applications of genomics include enhancement of current prognostic schemas, prediction of sensitivity or refractoriness to treatments, and conceptualization and selective application of targeted therapies. However, beyond these traditional clinical aspects, complex hierarchical clonal architecture has been uncovered and linked to the current concepts of leukemogenesis and stem cell biology. Detection of clonal mutations, otherwise typical of myelodysplastic syndrome, in the course of aplastic anemia (AA) and paroxysmal nocturnal hemoglobinuria has led to new pathogenic concepts in these conditions and created a new link between AA and its clonal complications, such as post-AA and paroxysmal nocturnal hemoglobinuria. Distinctions among founder vs subclonal mutations, types of clonal evolution (linear or branching), and biological features of individual mutations (sweeping, persistent, or vanishing) will allow for better predictions of the biologic impact they impart in individual cases. As clonal markers, mutations can be used for monitoring clonal dynamics of the stem cell compartment during physiologic aging, disease processes, and leukemic evolution.
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Affiliation(s)
- Jaroslaw P Maciejewski
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH
| | - Suresh K Balasubramanian
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH
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How Does the L884P Mutation Confer Resistance to Type-II Inhibitors of JAK2 Kinase: A Comprehensive Molecular Modeling Study. Sci Rep 2017; 7:9088. [PMID: 28831147 PMCID: PMC5567357 DOI: 10.1038/s41598-017-09586-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 07/26/2017] [Indexed: 01/17/2023] Open
Abstract
Janus kinase 2 (JAK2) has been regarded as an essential target for the treatment of myeloproliferative neoplasms (MPNs). BBT594 and CHZ868, Type-II inhibitors of JAK2, illustrate satisfactory efficacy in preclinical MPNs and acute lymphoblastic leukemia (ALL) models. However, the L884P mutation of JAK2 abrogates the suppressive effects of BBT594 and CHZ868. In this study, conventional molecular dynamics (MD) simulations, umbrella sampling (US) simulations and MM/GBSA free energy calculations were employed to explore how the L884P mutation affects the binding of BBT594 and CHZ868 to JAK2 and uncover the resistance mechanism induced by the L884P mutation. The results provided by the US and MD simulations illustrate that the L884P mutation enhances the flexibility of the allosteric pocket and alters their conformations, which amplify the conformational entropy change (−TΔS) and weaken the interactions between the inhibitors and target. Additionally, the structural analyses of BBT594 and CHZ868 in complex with the WT JAK2 illustrate that the drug tail with strong electronegativity and small size located in the allosteric pocket of JAK2 may enhance anti-resistance capability. In summary, our results highlight that both of the changes of the conformational entropies and enthalpies contribute to the L884P-induced resistance in the binding of two Type-II inhibitors into JAK2 kinase.
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Plo I, Bellanné-Chantelot C, Mosca M, Mazzi S, Marty C, Vainchenker W. Genetic Alterations of the Thrombopoietin/MPL/JAK2 Axis Impacting Megakaryopoiesis. Front Endocrinol (Lausanne) 2017; 8:234. [PMID: 28955303 PMCID: PMC5600916 DOI: 10.3389/fendo.2017.00234] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 08/28/2017] [Indexed: 12/31/2022] Open
Abstract
Megakaryopoiesis is an original and complex cell process which leads to the formation of platelets. The homeostatic production of platelets is mainly regulated and controlled by thrombopoietin (TPO) and the TPO receptor (MPL)/JAK2 axis. Therefore, any hereditary or acquired abnormality affecting this signaling axis can result in thrombocytosis or thrombocytopenia. Thrombocytosis can be due to genetic alterations that affect either the intrinsic MPL signaling through gain-of-function (GOF) activity (MPL, JAK2, CALR) and loss-of-function (LOF) activity of negative regulators (CBL, LNK) or the extrinsic MPL signaling by THPO GOF mutations leading to increased TPO synthesis. Alternatively, thrombocytosis may paradoxically result from mutations of MPL leading to an abnormal MPL trafficking, inducing increased TPO levels by alteration of its clearance. In contrast, thrombocytopenia can also result from LOF THPO or MPL mutations, which cause a complete defect in MPL trafficking to the cell membrane, impaired MPL signaling or stability, defects in the TPO/MPL interaction, or an absence of TPO production.
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Affiliation(s)
- Isabelle Plo
- INSERM UMR 1170, Gustave Roussy, Villejuif, France
- Université Paris-Saclay, UMR1170, Gustave Roussy, Villejuif, France
- Gustave Roussy, UMR1170, Villejuif, France
| | - Christine Bellanné-Chantelot
- INSERM UMR 1170, Gustave Roussy, Villejuif, France
- Department of Genetics, AP-HP Hôpitaux Universitaires Pitié Salpêtrière - Charles Foix, UPMC Univ Paris 06, Paris, France
| | - Matthieu Mosca
- INSERM UMR 1170, Gustave Roussy, Villejuif, France
- Université Paris-Saclay, UMR1170, Gustave Roussy, Villejuif, France
- Gustave Roussy, UMR1170, Villejuif, France
| | - Stefania Mazzi
- INSERM UMR 1170, Gustave Roussy, Villejuif, France
- Université Paris-Saclay, UMR1170, Gustave Roussy, Villejuif, France
- Université Paris-Diderot, Paris, France
| | - Caroline Marty
- INSERM UMR 1170, Gustave Roussy, Villejuif, France
- Université Paris-Saclay, UMR1170, Gustave Roussy, Villejuif, France
- Gustave Roussy, UMR1170, Villejuif, France
| | - William Vainchenker
- INSERM UMR 1170, Gustave Roussy, Villejuif, France
- Université Paris-Saclay, UMR1170, Gustave Roussy, Villejuif, France
- Gustave Roussy, UMR1170, Villejuif, France
- *Correspondence: William Vainchenker,
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18
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Genetic basis and molecular pathophysiology of classical myeloproliferative neoplasms. Blood 2016; 129:667-679. [PMID: 28028029 DOI: 10.1182/blood-2016-10-695940] [Citation(s) in RCA: 399] [Impact Index Per Article: 49.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Accepted: 12/06/2016] [Indexed: 02/07/2023] Open
Abstract
The genetic landscape of classical myeloproliferative neoplasm (MPN) is in large part elucidated. The MPN-restricted driver mutations, including those in JAK2, calreticulin (CALR), and myeloproliferative leukemia virus (MPL), abnormally activate the cytokine receptor/JAK2 pathway and their downstream effectors, more particularly the STATs. The most frequent mutation, JAK2V617F, activates the 3 main myeloid cytokine receptors (erythropoietin receptor, granulocyte colony-stimulating factor receptor, and MPL) whereas CALR or MPL mutants are restricted to MPL activation. This explains why JAK2V617F is associated with polycythemia vera, essential thrombocythemia (ET), and primary myelofibrosis (PMF) whereas CALR and MPL mutants are found in ET and PMF. Other mutations in genes involved in epigenetic regulation, splicing, and signaling cooperate with the 3 MPN drivers and play a key role in the PMF pathogenesis. Mutations in epigenetic regulators TET2 and DNMT3A are involved in disease initiation and may precede the acquisition of JAK2V617F. Other mutations in epigenetic regulators such as EZH2 and ASXL1 also play a role in disease initiation and disease progression. Mutations in the splicing machinery are predominantly found in PMF and are implicated in the development of anemia or pancytopenia. Both heterogeneity of classical MPNs and prognosis are determined by a specific genomic landscape, that is, type of MPN driver mutations, association with other mutations, and their order of acquisition. However, factors other than somatic mutations play an important role in disease initiation as well as disease progression such as germ line predisposition, inflammation, and aging. Delineation of these environmental factors will be important to better understand the precise pathogenesis of MPN.
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19
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Ornellas MH, De França Silva M, Solza C, De Lucena Gonçalves SBS, Silva De Almeida L, De Paula Ayres-Silva J, Seixas TL, Bastos EF, Liehr T, Alves G. Myelodysplastic syndrome without ring sideroblasts and with Janus kinase 2 gene mutation: An unusual case report. Mol Clin Oncol 2016; 5:227-230. [PMID: 27588186 DOI: 10.3892/mco.2016.947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 05/25/2016] [Indexed: 11/05/2022] Open
Abstract
Myelodysplastic syndrome (MDS) cases comprise a heterogeneous group of hematological disorders that are characterized by impaired hematopoiesis, with cytopenias of different grades and risk of developing acute myeloid leukemia. MDS may rarely be associated with thrombocytosis. In such cases, myelodysplasia and myeloproliferative disorders may overlap, making correct diagnosis difficult. We herein describe a case of MDS with thrombocytosis, Janus kinase 2 gene mutation-positive and Perls' staining-negative, which was initially classified as essential thrombocythemia (ET). This case highlights that MDS may be misdiagnosed as ET and inappropriate treatment may be initiated. Therefore, it is crucial to carefully combine all available data on morphology and immunophenotyping, and to perform the necessary molecular, cytogenetic and molecular cytogenetic analyses, in order to correctly diagnose this disease.
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Affiliation(s)
- Maria Helena Ornellas
- Department of Pathology, Laboratory of Circulating Markers, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil; Graduation Course in Medical Sciences, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil
| | - Monique De França Silva
- Department of Pathology, Laboratory of Circulating Markers, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil
| | - Cristiana Solza
- Department of Haematology, Pedro Ernesto University Hospital (HUPE), Rio de Janeiro State University (UERJ), Rio de Janeiro 20551-120, Brazil
| | | | - Liliane Silva De Almeida
- Department of Pathology, Laboratory of Circulating Markers, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil; Graduation Course in Medical Sciences, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil
| | | | - Taís Leite Seixas
- Cytogenetics Laboratory, Faculty of Medical Sciences, Rio de Janeiro State University (UERJ), Rio de Janeiro 20551-120, Brazil
| | - Elenice Ferreira Bastos
- Cytogenetics Laboratory, Faculty of Medical Sciences, Rio de Janeiro State University (UERJ), Rio de Janeiro 20551-120, Brazil; Department of Medical Genetic, Fernandes Figueira Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro 22250-020, Brazil
| | - Thomas Liehr
- Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, D-07743 Jena, Germany
| | - Gilda Alves
- Department of Pathology, Laboratory of Circulating Markers, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil; Graduation Course in Medical Sciences, Faculty of Medical Sciences (FCM), Rio de Janeiro 20550-170, Brazil; Research Coordination, National Cancer Institute (INCA), Ministry of Health, Rio de Janeiro 20230-130, Brazil
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20
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Malcovati L, Cazzola M. Recent advances in the understanding of myelodysplastic syndromes with ring sideroblasts. Br J Haematol 2016; 174:847-58. [PMID: 27391606 DOI: 10.1111/bjh.14215] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Myeloid neoplasms with ring sideroblasts are currently categorized within the myelodysplastic syndromes (MDS) or myelodysplastic/myeloproliferative neoplasms (MDS/MPN) in the World Health Organization classification. Recent findings have identified that the presence of ring sideroblasts in these disorders has a unique molecular basis, i.e., the somatic mutation of SF3B1, a gene encoding a splicing factor. Mutations of SF3B1 occur in up to 90% of patients with refractory anaemia with unilineage dysplasia (RARS) and 70% of those with refractory cytopenia with multilineage dysplasia and ring sideroblasts or RARS associated with marked thrombocytosis. Experimental evidence has shown that mutant SF3B1 results in the abnormal splicing of several genes, primarily due to misrecognition of 3' splice sites. The resulting aberrant mRNAs undergo nonsense-mediated mRNA decay (NMD), resulting in haploinsufficiency of canonical transcripts and protein expression. In addition, it is also possible that NMD-insensitive aberrant transcripts are translated into proteins with altered function. Patients with MDS carrying the SF3B1 mutation show a homogeneous disease phenotype characterized by isolated erythroid dysplasia and mild dysplasia in granulocytic or megakaryocytic lineages, supporting the notion that the SF3B1 mutation identifies a distinct entity within MDS. The available evidence suggests that these findings may have relevant impact on the diagnosis, classification and management of patients with these neoplasms.
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Affiliation(s)
- Luca Malcovati
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Department of Haematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
| | - Mario Cazzola
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Department of Haematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
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21
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Barbui T, Thiele J, Vannucchi AM, Tefferi A. Myeloproliferative neoplasms: Morphology and clinical practice. Am J Hematol 2016; 91:430-3. [PMID: 26718907 DOI: 10.1002/ajh.24288] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 12/22/2015] [Indexed: 12/26/2022]
Abstract
In myeloproliferative neoplasms (MPNs), controversy persists regarding the usefulness and reproducibility of bone marrow (BM) features. Disagreements concerning the WHO classification are mainly focused on the discrimination between essential thrombocythemia (ET) and prefibrotic/early primary myelofibrosis (prePMF) and prodromal polycythemia vera (PV). Criticism mostly refers to lack of standardization of distinctive BM features precluding correct morphological pattern recognition. The distinction between WHO-defined ET and prePMF is not trivial because outcome is significantly worse in prePMF. Morphology was generally considered to be non-specific for the diagnosis of PV. Recent studies have revealed under-diagnosis of morphologically and biologically consistent PV.
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Affiliation(s)
- Tiziano Barbui
- Research Foundation, Papa Giovanni XXIII Hospital; Bergamo Italy
| | - Jürgen Thiele
- Institute of pathology, University of Cologne; Cologne Germany
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22
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Sochacki AL, Fischer MA, Savona MR. Therapeutic approaches in myelofibrosis and myelodysplastic/myeloproliferative overlap syndromes. Onco Targets Ther 2016; 9:2273-86. [PMID: 27143923 PMCID: PMC4844455 DOI: 10.2147/ott.s83868] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The discovery of JAK2 (V617F) a decade ago led to optimism for a rapidly developing treatment revolution in Ph(-) myeloproliferative neoplasms. Unlike BCR-ABL, however, JAK2 was found to have a more heterogeneous role in carcinogenesis. Therefore, for years, development of new therapies was slow, despite standard treatment options that did not address the overwhelming symptom burden in patients with primary myelofibrosis (MF), post-essential thrombocythemia MF, post-polycythemia vera MF, and myelodysplastic syndrome (MDS)/myeloproliferative neoplasm (MPN) syndromes. JAK-STAT inhibitors have changed this, drastically ameliorating symptoms and ultimately beginning to show evidence of impact on survival. Now, the genetic foundations of myelofibrosis and MDS/MPN are rapidly being elucidated and contributing to targeted therapy development. This has been empowered through updated response criteria for MDS/MPN and refined prognostic scoring systems in these diseases. The aim of this article is to summarize concisely the current and rationally designed investigational therapeutics directed at JAK-STAT, hedgehog, PI3K-Akt, bone marrow fibrosis, telomerase, and rogue epigenetic signaling. The revolution in immunotherapy and novel treatments aimed at previously untargeted signaling pathways provides hope for considerable advancement in therapy options for those with chronic myeloid disease.
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Affiliation(s)
- Andrew L Sochacki
- Department of Internal Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Melissa A Fischer
- Department of Internal Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Michael R Savona
- Department of Internal Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt-Ingram Cancer Center, Nashville, TN, USA
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23
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Mughal TI, Cross NCP, Padron E, Tiu RV, Savona M, Malcovati L, Tibes R, Komrokji RS, Kiladjian JJ, Garcia-Manero G, Orazi A, Mesa R, Maciejewski JP, Fenaux P, Itzykson R, Mufti G, Solary E, List AF. An International MDS/MPN Working Group's perspective and recommendations on molecular pathogenesis, diagnosis and clinical characterization of myelodysplastic/myeloproliferative neoplasms. Haematologica 2016; 100:1117-30. [PMID: 26341525 DOI: 10.3324/haematol.2014.114660] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In the 2008 WHO classification, chronic myeloid malignancies that share both myelodysplastic and myeloproliferative features define the myelodysplastic/myeloproliferative group, which includes chronic myelomonocytic leukemia, juvenile myelomonocytic leukemia, atypical chronic myeloid leukemia, refractory anemia with ring sideroblasts and thrombocytosis, and myelodysplastic/myeloproliferative unclassified. With the notable exception of refractory anemia with ring sideroblasts and thrombocytosis, there is much overlap among the various subtypes at the molecular and clinical levels, and a better definition of these entities, an understanding of their biology and an identification of subtype-specific molecular or cellular markers are needed. To address some of these challenges, a panel comprised of laboratory and clinical experts in myelodysplastic/myeloproliferative was established, and four independent academic MDS/MPN workshops were held on: 9(th) March 2013, in Miami, Florida, USA; 6(th) December 2013, in New Orleans, Louisiana, USA; 13(th) June 2014 in Milan, Italy; and 5(th) December 2014 in San Francisco, USA. During these meetings, the current understanding of these malignancies and matters of biology, diagnosis and management were discussed. This perspective and the recommendations on molecular pathogenesis, diagnosis and clinical characterization for adult onset myelodysplastic/myeloproliferative is the result of a collaborative project endorsed and supported by the MDS Foundation.
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Affiliation(s)
| | | | - Eric Padron
- H. Lee Moffitt Cancer Center, Tampa, FL, USA
| | - Ramon V Tiu
- Cleveland Clinic Taussig Cancer Institute, OH, USA
| | - Michael Savona
- Vanderbilt University Medical Center, Nashville, TN, USA
| | - Luca Malcovati
- University of Pavia Medical School, S. Matteo University Hospital, Pavia, Italy
| | - Raoul Tibes
- Mayo Clinic Cancer Center, Scottsdale, AZ, USA
| | | | | | | | | | - Ruben Mesa
- Mayo Clinic Cancer Center, Scottsdale, AZ, USA
| | | | | | | | - Ghulam Mufti
- King's College Hospital, GKT School of Medicine, London, UK
| | | | - Alan F List
- H. Lee Moffitt Cancer Center, Tampa, FL, USA
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24
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Genomic landscape of megakaryopoiesis and platelet function defects. Blood 2016; 127:1249-59. [PMID: 26787733 DOI: 10.1182/blood-2015-07-607952] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 01/05/2016] [Indexed: 12/17/2022] Open
Abstract
Megakaryopoiesis is a complex, stepwise process that takes place largely in the bone marrow. At the apex of the hierarchy, hematopoietic stem cells undergo a number of lineage commitment decisions that ultimately lead to the production of polyploid megakaryocytes. On average, megakaryocytes release 10(11) platelets per day into the blood that repair vascular injuries and prevent excessive bleeding. This differentiation process is tightly controlled by exogenous and endogenous factors, which have been the topics of intense research in the hematopoietic field. Indeed, a skewing of megakaryocyte commitment and differentiation may entail the onset of myeloproliferative neoplasms and other preleukemic disorders together with acute megakaryoblastic leukemia, whereas quantitative or qualitative defects in platelet production can lead to inherited platelet disorders. The recent advent of next-generation sequencing has prompted mapping of the genomic landscape of these conditions to provide an accurate view of the underlying lesions. The aims of this review are to introduce the physiological pathways of megakaryopoiesis and to present landmark studies on acquired and inherited disorders that target them. These studies have not only introduced a new era in the fields of molecular medicine and targeted therapies but may also provide us with a better understanding of the mechanisms underlying normal megakaryopoiesis and thrombopoiesis that can inform efforts to create alternative sources of megakaryocytes and platelets.
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25
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Saeidi K. Myeloproliferative neoplasms: Current molecular biology and genetics. Crit Rev Oncol Hematol 2015; 98:375-89. [PMID: 26697989 DOI: 10.1016/j.critrevonc.2015.11.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Revised: 09/10/2015] [Accepted: 11/09/2015] [Indexed: 12/16/2022] Open
Abstract
Myeloproliferative neoplasms (MPNs) are clonal disorders characterized by increased production of mature blood cells. Philadelphia chromosome-negative MPNs (Ph-MPNs) consist of polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). A number of stem cell derived mutations have been identified in the past 10 years. These findings showed that JAK2V617F, as a diagnostic marker involving JAK2 exon 14 with a high frequency, is the best molecular characterization of Ph-MPNs. Somatic mutations in an endoplasmic reticulum chaperone, named calreticulin (CALR), is the second most common mutation in patients with ET and PMF after JAK2 V617F mutation. Discovery of CALR mutations led to the increased molecular diagnostic of ET and PMF up to 90%. It has been shown that JAK2V617F is not the unique event in disease pathogenesis. Some other genes' location such as TET oncogene family member 2 (TET2), additional sex combs-like 1 (ASXL1), casitas B-lineage lymphoma proto-oncogene (CBL), isocitrate dehydrogenase 1/2 (IDH1/IDH2), IKAROS family zinc finger 1 (IKZF1), DNA methyltransferase 3A (DNMT3A), suppressor of cytokine signaling (SOCS), enhancer of zeste homolog 2 (EZH2), tumor protein p53 (TP53), runt-related transcription factor 1 (RUNX1) and high mobility group AT-hook 2 (HMGA2) have also identified to be involved in MPNs phenotypes. Here, current molecular biology and genetic mechanisms involved in MNPs with a focus on the aforementioned factors is presented.
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Affiliation(s)
- Kolsoum Saeidi
- Department of Medical Genetics, Kerman University of Medical Sciences, Kerman, Iran.
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26
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Malcovati L, Rumi E, Cazzola M. Somatic mutations of calreticulin in myeloproliferative neoplasms and myelodysplastic/myeloproliferative neoplasms. Haematologica 2015; 99:1650-2. [PMID: 25420280 DOI: 10.3324/haematol.2014.113944] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Luca Malcovati
- Department of Hematology Oncology, Fondazione IRCCS Policlinico San Matteo, and Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Elisa Rumi
- Department of Hematology Oncology, Fondazione IRCCS Policlinico San Matteo, and Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Mario Cazzola
- Department of Hematology Oncology, Fondazione IRCCS Policlinico San Matteo, and Department of Molecular Medicine, University of Pavia, Pavia, Italy
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27
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Patnaik MM, Tefferi A. Refractory anemia with ring sideroblasts and RARS with thrombocytosis. Am J Hematol 2015; 90:549-59. [PMID: 25899435 DOI: 10.1002/ajh.24038] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 04/17/2015] [Indexed: 12/25/2022]
Abstract
DISEASE OVERVIEW Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include refractory anemia with ring sideroblasts (RARS) and RARS with thrombocytosis (RARS-T). DIAGNOSIS RARS is a lower risk myelodysplastic syndrome (MDS) with dysplasia limited to the erythroid lineage, <5% bone marrow (BM) blasts and ≥15% BM RS. RARS-T is a provisional entity in the MDS/MPN (myeloproliferative neoplasm) overlap syndromes, with diagnostic features of RARS, along with a platelet count ≥450 × 10(9)/L and large atypical megakaryocytes similar to those observed in BCR-ABL1 negative MPN. Mutations and Karyotype: Mutations in the SF3B1 gene are seen in ≥80% of patients with RARS and RARS-T, and strongly correlate with the presence of BM RS; RARS-T patients have additional mutations such as, JAK2V617F (∼60%), MPL (<5%), and CALR (<5%). Cytogenetic abnormalities are uncommon in both RARS and RARS-T. RISK STRATIFICATION Most patients with RARS are stratified into lower risk groups by the International Prognostic Scoring System (IPSS) for MDS and the revised IPSS. Disease outcome in RARS-T is better than that of RARS, but worse than that of essential thrombocytosis. Both RARS and RARS-T have a low risk of leukemic transformation. TREATMENT Anemia and iron overload are complications in both diseases and are managed similar to lower risk MDS. Aspirin therapy is reasonable in RARS-T, especially in the presence of JAK2V617F, but the value of platelet-lowering drugs is uncertain. Case reports of RARS-T therapy with lenalidomide warrant additional studies.
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Affiliation(s)
- Mrinal M. Patnaik
- Division of Hematology, Department of Internal Medicine; Mayo Clinic; Rochester Minnesota
| | - Ayalew Tefferi
- Division of Hematology, Department of Internal Medicine; Mayo Clinic; Rochester Minnesota
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28
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An international consortium proposal of uniform response criteria for myelodysplastic/myeloproliferative neoplasms (MDS/MPN) in adults. Blood 2015; 125:1857-65. [PMID: 25624319 DOI: 10.1182/blood-2014-10-607341] [Citation(s) in RCA: 131] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Myelodysplastic syndromes (MDS) and myeloproliferative neoplasms (MPN) are hematologically diverse stem cell malignancies sharing phenotypic features of both myelodysplastic syndromes and myeloproliferative neoplasms. There are currently no standard treatment recommendations for most adult patients with MDS/MPN. To optimize efforts to improve the management and disease outcomes, it is essential to identify meaningful clinical and biologic end points and standardized response criteria for clinical trials. The dual dysplastic and proliferative features in these stem cell malignancies define their uniqueness and challenges. We propose response assessment guidelines to harmonize future clinical trials with the principal objective of establishing suitable treatment algorithms. An international panel comprising laboratory and clinical experts in MDS/MPN was established involving 3 independent academic MDS/MPN workshops (March 2013, December 2013, and June 2014). These recommendations are the result of this collaborative project sponsored by the MDS Foundation.
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29
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Visconte V, Tiu RV, Rogers HJ. Pathogenesis of myelodysplastic syndromes: an overview of molecular and non-molecular aspects of the disease. Blood Res 2014; 49:216-27. [PMID: 25548754 PMCID: PMC4278002 DOI: 10.5045/br.2014.49.4.216] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Revised: 12/12/2014] [Accepted: 12/12/2014] [Indexed: 12/21/2022] Open
Abstract
Myelodysplastic syndromes (MDS) are a group of clonal disorders arising from hematopoietic stem cells generally characterized by inefficient hematopoiesis, dysplasia in one or more myeloid cell lineages, and variable degrees of cytopenias. Most MDS patients are diagnosed in their late 60s to early 70s. The estimated incidence of MDS in the United States and in Europe are 4.3 and 1.8 per 100,000 individuals per year, respectively with lower rates reported in some Asian countries and less well estimated in other parts of the world. Evolution to acute myeloid leukemia can occur in 10-15% of MDS patients. Three drugs are currently approved for the treatment of patients with MDS: immunomodulatory agents (lenalidomide), and hypomethylating therapy [HMT (decitabine and 5-azacytidine)]. All patients will eventually lose their response to therapy, and the survival outcome of MDS patients is poor (median survival of 4.5 months) especially for patients who fail (refractory/relapsed) HMT. The only potential curative treatment for MDS is hematopoietic cell transplantation. Genomic/chromosomal instability and various mechanisms contribute to the pathogenesis and prognosis of the disease. High throughput genetic technologies like single nucleotide polymorphism array analysis and next generation sequencing technologies have uncovered novel genetic alterations and increased our knowledge of MDS pathogenesis. We will review various genetic and non-genetic causes that are involved in the pathogenesis of MDS.
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Affiliation(s)
- Valeria Visconte
- Department of Translational Hematology and Oncology Research, Cleveland Clinic, Cleveland, OH, USA
| | - Ramon V Tiu
- Department of Translational Hematology and Oncology Research, Cleveland Clinic, Cleveland, OH, USA. ; Department of Hematologic Oncology and Blood Disorders, Cleveland Clinic, Cleveland, OH, USA
| | - Heesun J Rogers
- Department of Laboratory Medicine, Cleveland Clinic, Cleveland, OH, USA
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30
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Visconte V, Tabarroki A, Zhang L, Parker Y, Hasrouni E, Mahfouz R, Isono K, Koseki H, Sekeres MA, Saunthararajah Y, Barnard J, Lindner D, Rogers HJ, Tiu RV. Splicing factor 3b subunit 1 (Sf3b1) haploinsufficient mice display features of low risk Myelodysplastic syndromes with ring sideroblasts. J Hematol Oncol 2014; 7:89. [PMID: 25481243 PMCID: PMC4266210 DOI: 10.1186/s13045-014-0089-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 11/15/2014] [Indexed: 12/18/2022] Open
Abstract
Background The presence of somatic mutations in splicing factor 3b subunit 1 (SF3B1) in patients with Myelodysplastic syndromes with ring sideroblasts (MDS-RS) highlights the importance of the RNA-splicing machinery in MDS. We previously reported the presence of bone marrow (BM) RS in Sf3b1 heterozygous (Sf3b1+/−) mice which are rarely found in mouse models of MDS. Sf3b1+/− mice were originally engineered to study the interaction between polycomb genes and other proteins. Methods We used routine blood tests and histopathologic analysis of BM, spleen, and liver to evaluate the hematologic and morphologic characteristics of Sf3b1+/− mice in the context of MDS by comparing the long term follow-up (15 months) of Sf3b1+/− and Sf3b1+/+ mice. We then performed a comprehensive RNA-sequencing analysis to evaluate the transcriptome of BM cells from Sf3b1+/− and Sf3b1+/+ mice. Results Sf3b1+/− exhibited macrocytic anemia (MCV: 49.5 ± 1.6 vs 47.2 ± 1.4; Hgb: 5.5 ± 1.7 vs 7.2 ± 1.0) and thrombocytosis (PLTs: 911.4 ± 212.1 vs 878.4 ± 240.9) compared to Sf3b1+/+ mice. BM analysis showed dyserythropoiesis and occasional RS in Sf3b1+/− mice. The splenic architecture showed increased megakaryocytes with hyperchromatic nuclei, and evidence of extramedullary hematopoiesis. RNA-sequencing showed higher expression of a gene set containing Jak2 in Sf3b1+/− compared to Sf3b1+/+. Conclusions Our study indicates that Sf3b1+/− mice manifest features of low risk MDS-RS and may be relevant for preclinical therapeutic studies. Electronic supplementary material The online version of this article (doi:10.1186/s13045-014-0089-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Valeria Visconte
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue R40, Cleveland, OH, USA, 44195.
| | - Ali Tabarroki
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue R40, Cleveland, OH, USA, 44195.
| | - Li Zhang
- Department of Medicine, University of California, School of Medicine, San Francisco, CA, USA.
| | - Yvonne Parker
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue R40, Cleveland, OH, USA, 44195.
| | - Edy Hasrouni
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue R40, Cleveland, OH, USA, 44195.
| | - Reda Mahfouz
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue R40, Cleveland, OH, USA, 44195.
| | - Kyoichi Isono
- Center for Integrative Medical Sciences (IMS), RIKEN, Yokohama Institute, Yokohama, Japan.
| | - Haruhiko Koseki
- Center for Integrative Medical Sciences (IMS), RIKEN, Yokohama Institute, Yokohama, Japan.
| | - Mikkael A Sekeres
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue R40, Cleveland, OH, USA, 44195. .,Leukemia Program, Department of Hematology and Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
| | - Yogen Saunthararajah
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue R40, Cleveland, OH, USA, 44195. .,Leukemia Program, Department of Hematology and Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
| | - John Barnard
- Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH, USA.
| | - Daniel Lindner
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue R40, Cleveland, OH, USA, 44195.
| | - Heesun J Rogers
- Department of Laboratory Medicine, Cleveland Clinic, Cleveland, OH, USA.
| | - Ramon V Tiu
- Department of Translational Hematology and Oncology Research, Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue R40, Cleveland, OH, USA, 44195. .,Leukemia Program, Department of Hematology and Oncology, Taussig Cancer Institute, Cleveland Clinic, Cleveland, OH, USA.
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Zoi K, Cross NCP. Molecular pathogenesis of atypical CML, CMML and MDS/MPN-unclassifiable. Int J Hematol 2014; 101:229-42. [PMID: 25212680 DOI: 10.1007/s12185-014-1670-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Revised: 09/02/2014] [Accepted: 09/02/2014] [Indexed: 12/21/2022]
Abstract
According to the 2008 WHO classification, the category of myelodysplastic/myeloproliferative neoplasms (MDS/MPN) includes atypical chronic myeloid leukaemia (aCML), chronic myelomonocytic leukaemia (CMML), MDS/MPN-unclassifiable (MDS/MPN-U), juvenile myelomonocytic leukaemia (JMML) and a "provisional" entity, refractory anaemia with ring sideroblasts and thrombocytosis (RARS-T). The remarkable progress in our understanding of the somatic pathogenesis of MDS/MPN has made it clear that there is considerable overlap among these diseases at the molecular level, as well as layers of unexpected complexity. Deregulation of signalling plays an important role in many cases, and is clearly linked to more highly proliferative disease. Other mutations affect a range of other essential, interrelated cellular mechanisms, including epigenetic regulation, RNA splicing, transcription, and DNA damage response. The various combinations of mutations indicate a multi-step pathogenesis, which likely contributes to the marked clinical heterogeneity of these disorders. The delineation of complex clonal architectures may serve as the cornerstone for the identification of novel therapeutic targets and lead to better patient outcomes. This review summarizes some of the current knowledge of molecular pathogenetic lesions in the MDS/MPN subtypes that are seen in adults: atypical CML, CMML and MDS/MPN-U.
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Affiliation(s)
- Katerina Zoi
- Haematology Research Laboratory, Biomedical Research Foundation, Academy of Athens, Athens, Greece
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Malcovati L, Papaemmanuil E, Ambaglio I, Elena C, Gallì A, Della Porta MG, Travaglino E, Pietra D, Pascutto C, Ubezio M, Bono E, Da Vià MC, Brisci A, Bruno F, Cremonesi L, Ferrari M, Boveri E, Invernizzi R, Campbell PJ, Cazzola M. Driver somatic mutations identify distinct disease entities within myeloid neoplasms with myelodysplasia. Blood 2014; 124:1513-21. [PMID: 24970933 PMCID: PMC4148773 DOI: 10.1182/blood-2014-03-560227] [Citation(s) in RCA: 200] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 06/20/2014] [Indexed: 01/06/2023] Open
Abstract
Our knowledge of the genetic basis of myelodysplastic syndromes (MDS) and myelodysplastic/myeloproliferative neoplasms (MDS/MPN) has considerably improved. To define genotype/phenotype relationships of clinical relevance, we studied 308 patients with MDS, MDS/MPN, or acute myeloid leukemia evolving from MDS. Unsupervised statistical analysis, including the World Health Organization classification criteria and somatic mutations, showed that MDS associated with SF3B1-mutation (51 of 245 patients, 20.8%) is a distinct nosologic entity irrespective of current morphologic classification criteria. Conversely, MDS with ring sideroblasts with nonmutated SF3B1 segregated in different clusters with other MDS subtypes. Mutations of genes involved in DNA methylation, splicing factors other than SF3B1, and genes of the RAS pathway and cohesin complex were independently associated with multilineage dysplasia and identified a distinct subset (51 of 245 patients, 20.8%). No recurrent mutation pattern correlated with unilineage dysplasia without ring sideroblasts. Irrespective of driver somatic mutations, a threshold of 5% bone marrow blasts retained a significant discriminant value for identifying cases with clonal evolution. Comutation of TET2 and SRSF2 was highly predictive of a myeloid neoplasm characterized by myelodysplasia and monocytosis, including but not limited to, chronic myelomonocytic leukemia. These results serve as a proof of concept that a molecular classification of myeloid neoplasms is feasible.
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Affiliation(s)
- Luca Malcovati
- Department of Molecular Medicine, University of Pavia, Pavia, Italy; Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Elli Papaemmanuil
- Cancer Genome Project, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Ilaria Ambaglio
- Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Chiara Elena
- Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Anna Gallì
- Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Matteo G Della Porta
- Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy; Department of Internal Medicine, University of Pavia, Pavia, Italy
| | - Erica Travaglino
- Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Daniela Pietra
- Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Cristiana Pascutto
- Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Marta Ubezio
- Department of Molecular Medicine, University of Pavia, Pavia, Italy; Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Elisa Bono
- Department of Molecular Medicine, University of Pavia, Pavia, Italy; Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Matteo C Da Vià
- Department of Molecular Medicine, University of Pavia, Pavia, Italy; Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | - Angela Brisci
- Genomic Unit for the Diagnosis of Human Pathologies, San Raffaele Scientific Institute, Milan, Italy; and
| | - Francesca Bruno
- Genomic Unit for the Diagnosis of Human Pathologies, San Raffaele Scientific Institute, Milan, Italy; and
| | - Laura Cremonesi
- Genomic Unit for the Diagnosis of Human Pathologies, San Raffaele Scientific Institute, Milan, Italy; and
| | - Maurizio Ferrari
- Genomic Unit for the Diagnosis of Human Pathologies, San Raffaele Scientific Institute, Milan, Italy; and
| | - Emanuela Boveri
- Department of Human Pathology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
| | | | - Peter J Campbell
- Cancer Genome Project, Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Mario Cazzola
- Department of Molecular Medicine, University of Pavia, Pavia, Italy; Department of Hematology Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo, Pavia, Italy
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Rampal R, Levine RL. A primer on genomic and epigenomic alterations in the myeloproliferative neoplasms. Best Pract Res Clin Haematol 2014; 27:83-93. [DOI: 10.1016/j.beha.2014.07.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 07/11/2014] [Indexed: 01/13/2023]
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Kloth M, Buettner R. Changing histopathological diagnostics by genome-based tumor classification. Genes (Basel) 2014; 5:444-59. [PMID: 24879454 PMCID: PMC4094942 DOI: 10.3390/genes5020444] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 05/05/2014] [Accepted: 05/08/2014] [Indexed: 12/18/2022] Open
Abstract
Traditionally, tumors are classified by histopathological criteria, i.e., based on their specific morphological appearances. Consequently, current therapeutic decisions in oncology are strongly influenced by histology rather than underlying molecular or genomic aberrations. The increase of information on molecular changes however, enabled by the Human Genome Project and the International Cancer Genome Consortium as well as the manifold advances in molecular biology and high-throughput sequencing techniques, inaugurated the integration of genomic information into disease classification. Furthermore, in some cases it became evident that former classifications needed major revision and adaption. Such adaptations are often required by understanding the pathogenesis of a disease from a specific molecular alteration, using this molecular driver for targeted and highly effective therapies. Altogether, reclassifications should lead to higher information content of the underlying diagnoses, reflecting their molecular pathogenesis and resulting in optimized and individual therapeutic decisions. The objective of this article is to summarize some particularly important examples of genome-based classification approaches and associated therapeutic concepts. In addition to reviewing disease specific markers, we focus on potentially therapeutic or predictive markers and the relevance of molecular diagnostics in disease monitoring.
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Affiliation(s)
- Michael Kloth
- Institute of Pathology, University Hospital Cologne, Kerpener Str. 62, Cologne D-50937, Germany.
| | - Reinhard Buettner
- Institute of Pathology, University Hospital Cologne, Kerpener Str. 62, Cologne D-50937, Germany.
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Mughal TI, Girnius S, Rosen ST, Kumar S, Wiestner A, Abdel-Wahab O, Kiladjian JJ, Wilson WH, Van Etten RA. Emerging therapeutic paradigms to target the dysregulated Janus kinase/signal transducer and activator of transcription pathway in hematological malignancies. Leuk Lymphoma 2014; 55:1968-79. [PMID: 24206094 DOI: 10.3109/10428194.2013.863307] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Over the past decade, there has been increasing biochemical evidence that the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway is aberrantly activated in malignant cells from patients with a wide spectrum of cancers of the blood and immune systems. The emerging availability of small molecule inhibitors of JAK and other signaling molecules in the JAK/STAT pathway has allowed preclinical studies validating an important role of this pathway in the pathogenesis of many hematologic malignancies, and provided motivation for new strategies for treatment of these diseases. Here, a round-table panel of experts review the current preclinical and clinical landscape of the JAK/STAT pathway in acute lymphoid and myeloid leukemias, lymphomas and myeloma, and chronic myeloid neoplasms.
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Abstract
Refractory anemia with ring sideroblasts (RARS) is a subtype of myelodysplastic syndrome (MDS) characterized by 15% or more ring sideroblasts in the bone marrow according to the WHO classification. After Perls staining, ring sideroblasts are defined as erythroblasts in which there are 5 or more siderotic granules covering at least a third of the nuclear circumference. The iron deposited in perinuclear mitochondria of ring sideroblasts is present in the form of mitochondrial ferritin. The molecular basis of MDS with ring sideroblasts has remained unknown until recently. In 2011, whole exome sequencing studies revealed somatic mutations of SF3B1, a gene encoding a core component of RNA splicing machinery, in myelodysplasia with ring sideroblasts. The close relationship between SF3B1 mutation and ring sideroblasts is consistent with a causal relationship, and makes SF3B1 the first gene to be associated with a specific morphological feature in MDS. RARS is mainly characterized by isolated anemia due to ineffective erythropoiesis, and its clinical course is generally benign, although there is a tendency to worsening of anemia in most patients over time. By contrast, refractory cytopenia with multilineage dysplasia and ring sideroblasts (RCMD-RS) is characterized by pancytopenia and dysplasia in two or more myeloid cell lineages. More importantly, patients with RCMD-RS have a higher risk of developing bone marrow failure or progressing to acute myeloid leukemia (AML). Refractory anemia with ring sideroblasts (RARS-T) associated with marked thrombocytosis is a myelodysplastic/myeloproliferative neoplasm associated with both SF3B1 and JAK2 or MPL mutations. RARS-T may develop from an SF3B1 mutated RARS through the acquisition of a JAK2 or MPL mutations in a subclone of hematopoietic cells.
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Affiliation(s)
- Luca Malcovati
- Department of Molecular Medicine, University of Pavia, Pavia, Italy; Division of Hematology, Department of Hematology Oncology, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy
| | - Mario Cazzola
- Department of Molecular Medicine, University of Pavia, Pavia, Italy; Division of Hematology, Department of Hematology Oncology, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy.
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Kaneko K, Furuyama K, Fujiwara T, Kobayashi R, Ishida H, Harigae H, Shibahara S. Identification of a novel erythroid-specific enhancer for the ALAS2 gene and its loss-of-function mutation which is associated with congenital sideroblastic anemia. Haematologica 2013; 99:252-61. [PMID: 23935018 DOI: 10.3324/haematol.2013.085449] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Erythroid-specific 5-aminolevulinate synthase (ALAS2) is the rate-limiting enzyme for heme biosynthesis in erythroid cells, and a missense mutation of the ALAS2 gene is associated with congenital sideroblastic anemia. However, the gene responsible for this form of anemia remains unclear in about 40% of patients. Here, we identify a novel erythroid-specific enhancer of 130 base pairs in the first intron of the ALAS2 gene. The newly identified enhancer contains a cis-acting element that is bound by the erythroid-specific transcription factor GATA1, as confirmed by chromatin immunoprecipitation analysis in vivo and by electrophoretic mobility shift assay in vitro. A promoter activity assay in K562 human erythroleukemia cells revealed that the presence of this 130-base pair region increased the promoter activity of the ALAS2 gene by 10-15-fold. Importantly, two mutations, each of which disrupts the GATA-binding site in the enhancer, were identified in unrelated male patients with congenital sideroblastic anemia, and the lower expression level of ALAS2 mRNA in bone marrow erythroblasts was confirmed in one of these patients. Moreover, GATA1 failed to bind to each mutant sequence at the GATA-binding site, and each mutation abolished the enhancer function on ALAS2 promoter activity in K562 cells. Thus, a mutation at the GATA-binding site in this enhancer may cause congenital sideroblastic anemia. These results suggest that the newly identified intronic enhancer is essential for the expression of the ALAS2 gene in erythroid cells. We propose that the 130-base pair enhancer region located in the first intron of the ALAS2 gene should be examined in patients with congenital sideroblastic anemia in whom the gene responsible is unknown.
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Michiels JJ, Berneman Z, Schroyens W, Lam KH, De Raeve H. PVSG and WHO vs European Clinical, Molecular and Pathological Criteria for prefibrotic myeloproliferative neoplasms. World J Hematol 2013; 2:71-88. [DOI: 10.5315/wjh.v2.i3.71] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 06/18/2013] [Indexed: 02/05/2023] Open
Abstract
The Polycythemia Vera Study Group (PVSG), World Health Organization (WHO) and European Clinical, Molecular and Pathological (ECMP) classifications agree upon the diagnostic criteria for polycythemia vera (PV) and advanced primary myelofibrosis (MF). Essential thrombocythemia (ET) according to PVSG and 2007/2008 WHO criteria comprises three variants of JAK2V617F mutated ET when the ECMP criteria are applied. These include normocellular ET, hypercellular ET with features of early PV (prodromal PV), and hypercellular ET due to megakaryocytic, granulocytic myeloproliferation (ET.MGM). Evolution of prodromal PV into overt PV is common. Development of MF is rare in normocellular ET (WHO-ET) but rather common in hypercellular ET.MGM. The JAK2V617F mutation burden in heterozygous mutated normocellular ET and in heterozygous/homozygous or homozygous mutated PV and ET.MGM is of major prognostic significance. JAK2/MPL wild type ET associated with prefibrotic primary megakaryocytic and granulocytic myeloproliferation (PMGM) is characterized by densely clustered immature dysmorphic megakaryocytes with bulky (bulbous) hyperchromatic nuclei, which are never seen in JAK2V617F mutated ET, and PV and also not in MPL515 mutated normocellular ET (WHO-ET). JAK2V617 mutation burden, spleen size, LDH, circulating CD34+ cells, and pre-treatment bone marrow histopathology are mandatory to stage the myeloproliferative neoplasms ET, PV, PMGM for proper prognosis assessment and therapeutic implications. MF itself is not a disease because reticulin fibrosis and reticulin/collagen fibrosis are secondary responses of activated polyclonal fibroblasts to cytokines released from the clonal myeloproliferative granulocytic and megakaryocytic progenitor cells in ET.MGM, PV and PMGM.
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Greenberg PL, Attar E, Bennett JM, Bloomfield CD, Borate U, De Castro CM, Deeg HJ, Frankfurt O, Gaensler K, Garcia-Manero G, Gore SD, Head D, Komrokji R, Maness LJ, Millenson M, O'Donnell MR, Shami PJ, Stein BL, Stone RM, Thompson JE, Westervelt P, Wheeler B, Shead DA, Naganuma M. Myelodysplastic syndromes: clinical practice guidelines in oncology. J Natl Compr Canc Netw 2013; 11:838-74. [PMID: 23847220 PMCID: PMC4000017 DOI: 10.6004/jnccn.2013.0104] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The myelodysplastic syndromes (MDS) represent a heterogeneous group of clonal hematopoietic disorders characterized by cytopenias, dysplasia in one or more myeloid lineages, and the potential for development of acute myeloid leukemia. These disorders primarily affect older adults. The NCCN Clinical Practice Guidelines in Oncology for MDS provide recommendations on the diagnostic evaluation and classification of MDS, risk evaluation according to established prognostic assessment tools (including the new revised International Prognostic Scoring System), treatment options according to risk categories, and management of related anemia.
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Abstract
Myelodysplastic syndromes (MDS) were first presented as a separate entity in hematology in 1982 by the French-American-British (FAB) group. Although widely accepted, this classification was revised in 2001 and again in 2008 by the World Health Organization (WHO). During that time, a great effort was made by diagnostic entities of world renown as well as by other research groups and individuals to establish a reliable prognostic system. Today, two systems are accepted by the hematologic community: the International World Prognostic Scoring System (IPSS) and the WHO Prognostic Scoring System (WPSS). Almost from the beginning, it was assumed that MDS are clonal disorders. Cytogenetics not only proved the clonality in the majority of cases but also greatly contributed to the stratification of patients into risk categories. With the progress made in treatment for MDS, comorbidities became an important part of the integral pretreatment consideration, as patients with a high index of comorbidity evaluation very often do not benefit from treatment. Recent advances in the diagnostic and prognostic evaluation of MDS patients were achieved by studying the effect of age in different MDS subgroups and the role of molecular markers in predicting clinical evolution.
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Affiliation(s)
- Photis Beris
- Department of Internal Medicine, School of Medicine, Geneva University, Geneva, Switzerland.
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Broséus J, Alpermann T, Wulfert M, Florensa Brichs L, Jeromin S, Lippert E, Rozman M, Lifermann F, Grossmann V, Haferlach T, Germing U, Luño E, Girodon F, Schnittger S. Age, JAK2V617F and SF3B1 mutations are the main predicting factors for survival in refractory anaemia with ring sideroblasts and marked thrombocytosis. Leukemia 2013; 27:1826-31. [DOI: 10.1038/leu.2013.120] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 04/10/2013] [Indexed: 01/05/2023]
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Abstract
The association between somatic JAK2 mutation and myeloproliferative neoplasms (MPNs) is now well established. However, because JAK2 mutations are associated with heterogeneous clinical phenotypes and often occur as secondary genetic events, some aspects of JAK2 mutation biology remain to be understood. We recently described a germline JAK2V617I mutation in a family with hereditary thrombocytosis and herein characterize the hematopoietic and signaling impact of JAK2V617I. Through targeted sequencing of MPN-associated mutations, exome sequencing, and clonality analysis, we demonstrate that JAK2V617I is likely to be the sole driver mutation in JAK2V617I-positive individuals with thrombocytosis. Phenotypic hematopoietic stem cells (HSCs) were increased in the blood and bone marrow of JAK2V617I-positive individuals and were sustained at higher levels than controls after xenotransplantation. In signaling and transcriptional assays, JAK2V617I demonstrated more activity than wild-type JAK2 but substantially less than JAK2V617F. After cytokine stimulation, JAK2V617I resulted in markedly increased downstream signaling compared with wild-type JAK2 and comparable with JAK2V617F. These findings demonstrate that JAK2V617I induces sufficient cytokine hyperresponsiveness in the absence of other molecular events to induce a homogeneous MPN-like phenotype. We also provide evidence that the JAK2V617I mutation may expand the HSC pool, providing insights into both JAK2 mutation biology and MPN disease pathogenesis.
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Dysregulation of JAK-STAT pathway in hematological malignancies and JAK inhibitors for clinical application. Biomark Res 2013; 1:5. [PMID: 24252238 PMCID: PMC3776247 DOI: 10.1186/2050-7771-1-5] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Accepted: 09/14/2012] [Indexed: 12/15/2022] Open
Abstract
JAK-STAT (Janus associated kinase-signal transducer and activator of transcription) pathway plays a critical role in transduction of extracellular signals from cytokines and growth factors involved in hematopoiesis, immune regulation, fertility, lactation, growth and embryogenesis. JAK family contains four cytoplasmic tyrosine kinases, JAK1-3 and Tyk2. Seven STAT proteins have been identified in human cells, STAT1-6, including STAT5a and STAT5b. Negative regulators of JAK-STAT pathways include tyrosine phosphatases (SHP1 and 2, CD45), protein inhibitors of activated STATs (PIAS), suppressors of cytokine signaling (SOCS) proteins, and cytokine-inducible SH2-containing protein (CIS). Dysregulation of JAK-STAT pathway have been found to be key events in a variety of hematological malignancies. JAK inhibitors are among the first successful agents reaching clinical application. Ruxolitinib (Jakafi), a non-selective inhibitor of JAK1 & 2, has been approved by FDA for patients with intermediate to high risk primary or secondary myelofibrosis. This review will also summarize early data on selective JAK inhibitors, including SAR302503 (TG101348), lestaurtinib (CEP701), CYT387, SB1518 (pacritinib), LY2784544, XL019, BMS-911543, NS-018, and AZD1480.
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Abstract
Myelodysplastic syndromes (MDS) are malignant clonal disorders of haematopoietic stem cells and their microenvironment, affecting older individuals (median age ∼70 years). Unique features that are associated with MDS - but which are not necessarily present in every patient with MDS - include excessive apoptosis in maturing clonal cells, a pro-inflammatory bone marrow microenvironment, specific chromosomal abnormalities, abnormal ribosomal protein biogenesis, the presence of uniparental disomy, and mutations affecting genes involved in proliferation, methylation and epigenetic modifications. Although emerging insights establish an association between molecular abnormalities and the phenotypic heterogeneity of MDS, their origin and progression remain enigmatic.
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Affiliation(s)
- Azra Raza
- Myelodysplastic Syndromes Center, Columbia University Medical Center, Milstein Hospital Building, 6N-435, 177 Fort Washington Avenue, New York, New York 10032, USA.
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Bench AJ, White HE, Foroni L, Godfrey AL, Gerrard G, Akiki S, Awan A, Carter I, Goday-Fernandez A, Langabeer SE, Clench T, Clark J, Evans PA, Grimwade D, Schuh A, McMullin MF, Green AR, Harrison CN, Cross NCP. Molecular diagnosis of the myeloproliferative neoplasms: UK guidelines for the detection ofJAK2V617F and other relevant mutations. Br J Haematol 2012; 160:25-34. [DOI: 10.1111/bjh.12075] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Anthony J. Bench
- Molecular Malignancy Laboratory and Haemato-Oncology Diagnostic Service; Cambridge University Hospitals NHS Foundation Trust; Cambridge; UK
| | | | - Letizia Foroni
- Imperial Molecular Pathology; Imperial College Academic Health Science Centre; London; UK
| | - Anna L. Godfrey
- Cambridge Institute for Medical Research; Department of Haematology; University of Cambridge; Cambridge; UK
| | - Gareth Gerrard
- Imperial Molecular Pathology; Imperial College Academic Health Science Centre; London; UK
| | - Susanna Akiki
- West Midlands Regional Genetics Laboratory; Birmingham Women's NHS Foundation Trust; Birmingham; UK
| | - Abida Awan
- Molecular Diagnostics Centre; Manchester Royal Infirmary; Manchester; UK
| | - Ian Carter
- Nottingham University Hospitals NHS Trust; Nottingham; UK
| | - Andrea Goday-Fernandez
- Molecular Malignancy Laboratory and Haemato-Oncology Diagnostic Service; Cambridge University Hospitals NHS Foundation Trust; Cambridge; UK
| | | | | | - Jordan Clark
- UK NEQAS for Leucocyte Immunophenotyping; Sheffield; UK
| | - Paul A. Evans
- HMDS, Leeds Institute of Oncology; St. James's University Hospital; Leeds; UK
| | - David Grimwade
- Department of Medical and Molecular Genetics; King's College London School of Medicine; London; UK
| | - Anna Schuh
- Oxford Cancer and Haematology Centre; Churchill Hospital; Oxford; UK
| | | | - Anthony R. Green
- Cambridge Institute for Medical Research; Department of Haematology; University of Cambridge; Cambridge; UK
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Vannucchi AM, Pieri L, Susini MC, Guglielmelli P. BCR-ABL1-negative chronic myeloid neoplasms: an update on management techniques. Future Oncol 2012; 8:575-93. [PMID: 22646772 DOI: 10.2217/fon.12.50] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Recent discoveries concerning mutations associated with chronic myeloproliferative neoplasms have modified our understanding of the biology of these incurable diseases and guided us to the development of inhibitors active on the constitutively activated JAK-STAT pathway. Concurrently, numerous studies dealt with clinical issues; it led to a revised WHO classification; clarified the role of mutated JAK2 and leukocytosis in the pathogenesis of cardiovascular events; allowed the development of risk prognostic scores and tools for monitoring response to therapy; and resulted in completion of Phase III trials with JAK2 inhibitor in myelofibrosis. All these results hold the promise of improving patient prognostication and therapeutic approach, with the aim of efficiently preventing disease-associated complications and, hopefully, to improve the dismal survival associated with myelofibrosis. This review discusses how to manage, according to current clinical practice, the steps of diagnosis, prognostication and therapeutic choices in myeloproliferative neoplasm patients.
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Affiliation(s)
- Alessandro M Vannucchi
- Section of Hematology, Department of Critical Care, University of Florence, Largo Brambilla 3, 50134 Florence, Italy.
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Nussenzveig RH, Burjanivova T, Salama ME, Ogilvie NW, Marcinek J, Plank L, Agarwal AM, Perkins SL, Prchal JT. Detection ofJAK2mutations in paraffin marrow biopsies by high resolution melting analysis: identification ofL611Salone and in cis withV617Fin polycythemia vera. Leuk Lymphoma 2012; 53:2479-86. [PMID: 22642932 DOI: 10.3109/10428194.2012.697562] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Roberto H Nussenzveig
- ARUP Laboratories and Department of Pathology, University of Utah, Salt Lake City, UT 84108, USA.
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48
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Broseus J, Florensa L, Zipperer E, Schnittger S, Malcovati L, Richebourg S, Lippert E, Cermak J, Evans J, Mounier M, Raya JM, Bailly F, Gattermann N, Haferlach T, Garand R, Allou K, Besses C, Germing U, Haferlach C, Travaglino E, Luno E, Pinan MA, Arenillas L, Rozman M, Perez Sirvent ML, Favre B, Guy J, Alonso E, Ahwij N, Jerez A, Hermouet S, Maynadié M, Cazzola M, Girodon F. Clinical features and course of refractory anemia with ring sideroblasts associated with marked thrombocytosis. Haematologica 2012; 97:1036-41. [PMID: 22532522 DOI: 10.3324/haematol.2011.053918] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Refractory anemia with ring sideroblasts associated with marked thrombocytosis was proposed as a provisional entity in the 2001 World Health Organization classification of myeloid neoplasms and also in the 2008 version, but its existence as a single entity is contested. We wish to define the clinical features of this rare myelodysplastic/myeloproliferative neoplasm and to compare its clinical outcome with that of refractory anemia with ring sideroblasts and essential thrombocythemia. DESIGN AND METHODS We conducted a collaborative retrospective study across Europe. Our database included 200 patients diagnosed with refractory anemia with ring sideroblasts and marked thrombocytosis. For each of these patients, each patient diagnosed with refractory anemia with ring sideroblasts was matched for age and sex. At the same time, a cohort of 454 patients with essential thrombocythemia was used to compare outcomes of the two diseases. RESULTS In patients with refractory anemia with ring sideroblasts and marked thrombocytosis, depending on the Janus Kinase 2 V617F mutational status (positive or negative) or platelet threshold (over or below 600 × 10(9)/L), no difference in survival was noted. However, these patients had shorter overall survival and leukemia-free survival with a lower risk of thrombotic complications than did patients with essential thrombocythemia (P<0.001) but better survival (P<0.001) and a higher risk of thrombosis (P=0.039) than patients with refractory anemia with ring sideroblasts. CONCLUSIONS The clinical course of refractory anemia with ring sideroblasts and marked thrombocytosis is better than that of refractory anemia with ring sideroblasts and worse than that of essential thrombocythemia. The higher risk of thrombotic events in this disorder suggests that anti-platelet therapy might be considered in this subset of patients. From a clinical point of view, it appears to be important to consider refractory anemia with ring sideroblasts and marked thrombocytosis as a distinct entity.
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Affiliation(s)
- Julien Broseus
- Service d'Hématologie Biologique, Hôpital du Bocage, CHU de Dijon, Dijon, France
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49
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Gnanasambandan K, Sayeski PP. A structure-function perspective of Jak2 mutations and implications for alternate drug design strategies: the road not taken. Curr Med Chem 2012; 18:4659-73. [PMID: 21864276 DOI: 10.2174/092986711797379267] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Revised: 08/19/2011] [Accepted: 08/22/2011] [Indexed: 01/13/2023]
Abstract
Jak2 is a non-receptor tyrosine kinase that is involved in the control of cellular growth and proliferation. Due to its significant role in hematopoiesis, Jak2 is a frequent target for mutations in cancer, especially myeloid leukemia, lymphoid leukemia and the myeloproliferative neoplasms (MPN). These mutations are common amongst different populations all over the world and there is a great deal of effort to develop therapeutic drugs for the affected patients. Jak2 mutations, whether they are point, deletion, or gene fusion, most commonly result in constitutive kinase activation. Here, we explore the structure-function relation of various Jak2 mutations identified in cancer and understand how they disrupt Jak2 regulation. Current Jak2 inhibitors target the highly conserved active site in the kinase domain and therefore, these inhibitors may lack specificity. Based on our knowledge regarding structure-function correlations as they pertain to regulation of Jak2 kinase activity, an alternative approach for specific Jak2 targeting could be via allosteric inhibitor design. Successful reports of allosteric inhibitors developed against other kinases provide precedent for the development of Jak2 allosteric inhibitors. Here, we suggest plausible target sites in the Jak2 structure for allosteric inhibition. Such targets include the type II inhibitor pocket and substrate binding site in the kinase domain, the kinase-pseudokinase domain interface, SH2-JH2 linker region and the FERM domain. Thus, future Jak2 inhibitors that target these sites via allosteric mechanisms may provide alternative therapeutic strategies to existing ATP competitive inhibitors.
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Affiliation(s)
- K Gnanasambandan
- Department of Physiology and Functional Genomics, University of Florida College of Medicine, Gainesville, USA
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Anastasi J. The myeloproliferative neoplasms including the eosinophilia-related myeloproliferations associated with tyrosine kinase mutations: changes and issues in classification and diagnosis criteria. Semin Diagn Pathol 2012; 28:304-13. [PMID: 22195408 DOI: 10.1053/j.semdp.2011.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The classification and diagnostic criteria of the myeloproliferative neoplasms have changed significantly in the 2008 World Health Organization monograph on the classification of hematologic malignancies. Many of the changes arose from the findings that the different malignancies are associated with abnormal cell signaling because of translocations or mutations in genes for protein tryosine kinases involved in the normal growth and regulation of hematopoietic cells. These include ABL1, PDGFRA, PDGFRB, FGFR1, JAK2, MPL, and KIT. The new classification attempts to reflect the related molecular pathogenesis of the different entities and incorporates the identification of the molecular defects into the diagnostic criteria for some of the individual diseases. Issues concerning the new classification are discussed, and the new diagnostic criteria are reviewed and commented upon.
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Affiliation(s)
- John Anastasi
- Hematopathology Section, Department of Pathology, University of Chicago, Chicago, Illinois 60637, USA.
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